Malaria is one of the most prevalent infections in tropical and subtropical areas throughout the world. Malaria infections lead to severe illnesses in hundreds of millions of individuals worldwide, leading to death in millions of individuals, primarily in developing and emerging countries every year. The widespread occurrence and elevated incidence of malaria are a consequence of the increasing numbers of drug-resistant parasites and insecticide-resistant parasite vectors. Other factors include environmental and climatic changes, civil disturbances, and increased mobility of populations.
Malaria is caused by the mosquito-borne hematoprotozoan parasites belonging to the genus Plasmodium. Four species of Plasmodium protozoa (P. falciparum, P. vivax, P. ovale and P. malariae) are responsible for the disease in man; many others cause disease in animals, such as P. yoelii and P. berghei in mice. P. falciparum accounts for the majority of infections and is the most lethal type, sometimes called “tropical malaria”. Malaria parasites have a life cycle consisting of several stages. Each stage is able to induce specific immune responses directed against the corresponding occurring stage-specific antigens.
There is a need for improved antigenic compositions suitable for stimulating an immune response to malaria.